Clinical predictors of postoperative hemoglobin drift.

Background: The decision to transfuse red blood cells in surgical patients should be based on multiple clinical variables, rather than on isolated hemoglobin (Hb) measurements alone. An important but often unrecognized clinical variable is the postoperative downward drift in Hb concentration (Hb drift), but the etiology, predictors, and time course of Hb drift are not well understood.

Study Design And Methods: Data were retrospectively collected for patients who did not receive postoperative transfusion.